For both China, U.S., lessons in air pollution and surging energy use

The study released Thursday compared the world's two biggest energy consumers, the United States and China.

One of the most important lessons? It makes more sense to try to prevent pollution, rather than clean it up afterward.

The study also found that national controls are important though focusing on small sources of pollution also can have a broad impact.

Los Angeles was compared with the Chinese city of Dalian, both port cities, while Pittsburgh was stacked against Huainan, both coal-rich centers of industry.

According to the study, the result of a 2 1/2 year collaboration between U.S. and Chinese academies of engineering and sciences, both countries still have major problems with dirty air and must improve their energy efficiency.

Los Angeles' serious smog problems are well-studied and the city uses federal and local planning to try to address it. On the other hand, its over-reliance on cars and sprawling development have not helped, the study said.

Pittsburgh began attacking its smog problem in the 1940s, but only after early reliance on coal that overlooked the consequences of air pollution.

"An important lesson learned is that air pollution damage imposes major economic costs, through premature mortality, increased sickness and lost productivity, as well as decreased crop yields and ecosystem impacts," the report says. "Cost-benefit analyses in the U.S. show that emission reduction programs have provided much greater benefits than their costs, by a ratio of up to 40 to 1, according to some estimates."

U.S. efforts in the past 30 years have reduced the biggest risks from lead in gasoline, acid rain-causing sulfur dioxide and some soot pollution, the study says, though in some areas the Chinese are ahead — such as in research on coal gasification — to use it more efficiently and emit less pollution. Coal gasification is the conversion of coal into gaseous fuels.

By contrast, Dalian's urban planning to minimize sprawl and its local transit — more bicycles, pedestrians, buses and light rail — is seen as an example for Los Angeles.

"In China, they have very good rules but they don't have good enforcement for air pollution," said John Watson, a co-chairman of the report and professor at the Desert Research Institute. "They're making a lot of the same mistakes we made in our air pollution history. You can just see the parallels: they're building more highways and encouraging more sprawl."

Though fossil fuel burning dominates both nations, a major difference is the source for roughly two-thirds of their energy needs: for China, which has some of the world's filthiest air, it is coal; for the United States, it is petroleum and natural gas.

China is the world's biggest emitter of sulfur dioxide; both countries lead the world in their emissions of industrial carbon dioxide, a heat-trapping gas blamed for warming the atmosphere like a greenhouse. But the study skirted the issue of global warming.

Another recommendation is that the Chinese government focus on collecting and providing good quality data on air pollution and energy uses. According to the Organization for Economic Co-operation and Development, by 2020 China will have 20 million cases of respiratory illness a year because of air pollution.